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Discussion Starter · #1 ·
Well I’m back, still haven’t had any luck finding a first truck but I’m back asking for thoughts on another truck I’m looking at, here are the things I noticed while test driving it, knowing it has misfires;


Took 2 cranks to start up
Motor shakes on idle
Idles hard
Shakes when shifting into Neutral and 2nd, only two I tested
Looses lots of power when releasing pressure on gas pedal
Drives fine otherwise (steering,brakes)
Abs light on, check engine came on a few minutes into drive
Spark plugs replaced recently, done correctly and still changed nothing
Has 5.7L V8 with cold air intake, 2 cherry pack exhaust. 170k miles. Wants 3k for it, will talk him down as he said he’s flexible on price. I know I’m missing some things.

And my concern is it’s going to be to much for me.Luckily labor costs aren’t an issue for me but I don’t want to end up with a blown motor or some other crazy expensive problem. Please let me know your thoughts
 

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Discussion Starter · #3 ·
well the guy told me he scanned it and it just came up with misfire codes? If I remember right
 

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well the guy told me he scanned it and it just came up with misfire codes? If I remember right
Well I would not buy the truck without at least doing a compression test and a combustion leak test. You can pick up a compression tester and combustion leak test kit from Harbor Freight, good to have on hand.
 

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first of all, what kind of truck is it? the chevy 350 was first built in what the 60's? and ended production some time in the mid 2000's with trucks built in Mexico.

if it had a distributor, change it and the rotor inside. check for play. if there is play you need to change the base as well.

if it doesn't have a distributor then IDK, could be many things.

first we need to know what your looking at. misfire codes are no big deal if that distributor is old as it's full of corrosion... like this or worse.

Auto part Gas Machine Fashion accessory Electric blue

this is a 8 or 9 year old distributor n rotor off of my 97, k1500 Burb with the 5.7L (350). the truck had absoluty terrible misfires and would not stay running. a new distributor (with BRASS contacts) n rotor fixed it 100%.

Al
 

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if you buy this truck that's not running right at $3000 it better be in very good conditions and mostly free of rust, especially on the body. the frame should be solid.

get rid of cold air intake and put the original cold air intake back on (they come with one.) removing the oem air box that pulls cool air in from the fender actually pulls warm air in from the engine bay.
 

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‘01 Silverado 2500HD 8.1/Allison 5sp xcab long bed
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Check the trouble codes and report back.
 

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Discussion Starter · #8 ·
first of all, what kind of truck is it? the chevy 350 was first built in what the 60's? and ended production some time in the mid 2000's with trucks built in Mexico.

if it had a distributor, change it and the rotor inside. check for play. if there is play you need to change the base as well.

if it doesn't have a distributor then IDK, could be many things.

first we need to know what your looking at. misfire codes are no big deal if that distributor is old as it's full of corrosion... like this or worse.

View attachment 170328
this is a 8 or 9 year old distributor n rotor off of my 97, k1500 Burb with the 5.7L (350). the truck had absoluty terrible misfires and would not stay running. a new distributor (with BRASS contacts) n rotor fixed it 100%.

Al
I’m looking at an 1998 K1500 with the 350
 

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Discussion Starter · #9 ·
if you buy this truck that's not running right at $3000 it better be in very good conditions and mostly free of rust, especially on the body. the frame should be solid.

get rid of cold air intake and put the original cold air intake back on (they come with one.) removing the oem air box that pulls cool air in from the fender actually pulls warm air in from the engine bay.
It is very clean with little rust and he has a another new painted body panel to go with it, and okay if I end up buying it that will be the first thing to go
 

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ahhh your golden then! these are simple engines that have stood the test of time. I would use the fact that its dosent run right to try and get $1000 dropped off the asking price. it wont cost you a grand to get it fixed. distributors are cheap but there are other causes for a misfire.

low fuel pressure can also cause a misfire. it sparks and theres no fuel to ignite and so it doesn't fire. that's a misfire.

I doubt with such low mileage that the timing is out. it's possible but unlikely.

you dont really want to try to diagnose it in front of the owner but a fuel pressure test is easy to do. same with plugging in an obd2 reader and seeing what the codes are and also reading the live data can give you lots of insite to the potential problems.

good luck!
 

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98 gmc k1500 5.7
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you have a lot of great suggestions here jaxson , i also own a 98 with 5.7 , i have done a lot of work to it , not because it was abused , but because its 24 yrs old , , and alot of things are worn out, if the body is good , your ahead of the game already, misfires could be something as simple and cap and rotor like the gawd said, and furious mentioned getting a compression and leakdown test , also great idea, cowboy also made a good point about scanning it for codes, i think if you listen to these guys and the truck checks out and is what you want then go for it.
 

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Discussion Starter · #12 ·
ahhh your golden then! these are simple engines that have stood the test of time. I would use the fact that its dosent run right to try and get $1000 dropped off the asking price. it wont cost you a grand to get it fixed. distributors are cheap but there are other causes for a misfire.

low fuel pressure can also cause a misfire. it sparks and theres no fuel to ignite and so it doesn't fire. that's a misfire.

I doubt with such low mileage that the timing is out. it's possible but unlikely.

you dont really want to try to diagnose it in front of the owner but a fuel pressure test is easy to do. same with plugging in an obd2 reader and seeing what the codes are and also reading the live data can give you lots of insite to the potential problems.

good luck!
I forgot to mention it would barely go past 25-35mph.. I don’t know if this changes anything or it still goes with the issues?
 

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Discussion Starter · #13 ·
you have a lot of great suggestions here jaxson , i also own a 98 with 5.7 , i have done a lot of work to it , not because it was abused , but because its 24 yrs old , , and alot of things are worn out, if the body is good , your ahead of the game already, misfires could be something as simple and cap and rotor like the gawd said, and furious mentioned getting a compression and leakdown test , also great idea, cowboy also made a good point about scanning it for codes, i think if you listen to these guys and the truck checks out and is what you want then go for it.
Okay thanks I’ll definitely try to get some more tests done and hopefully it goes well
 

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Fuel pump.... you have many indications of a failed fuel pump. play it like it needs a new motor and spend maybe a couple hundred having a fuel pump put in. a good fuel pump is Delphi or acdelco and they alone are around $100. it's a good practice to replace everything while your in there so a couple hundred in parts and then labour if your having it done. it's possible the old fuel lines might need replacing especially at the fitting..... its not the end of the world.

I bet the misfires are simply because its starving for fuel.

get R done!

Al
 

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Hell for what it's worth, it could be as simple as a plugged up fuel filter, replace this first! its only $10. be careful with those fuel lines....

If I was in your position and was having a shop do these jobs I would have them do this....

fuel pump and its hanger
fuel filter
anything related to fixing the fuel pump
the entire distributor since it's probably original,
regular paper air filter and oh ya back in the OEM box
spark plugs and wires.
possiboy O2 sensors simply because they are probably also original and getting weak.

I might be missing something but if you change all those things it would have a complete tune up and should be a great running truck. after doing all that on my burb I get 17.8 MPG and I couodnt believe it!

Al
 

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Discussion Starter · #16 ·
Hell for what it's worth, it could be as simple as a plugged up fuel filter, replace this first! its only $10. be careful with those fuel lines....

If I was in your position and was having a shop do these jobs I would have them do this....

fuel pump and its hanger
fuel filter
anything related to fixing the fuel pump
the entire distributor since it's probably original,
regular paper air filter and oh ya back in the OEM box
spark plugs and wires.
possiboy O2 sensors simply because they are probably also original and getting weak.

I might be missing something but if you change all those things it would have a complete tune up and should be a great running truck. after doing all that on my burb I get 17.8 MPG and I couodnt believe it!

Al
Alright thanks for the help
 

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Discussion Starter · #17 ·
Hell for what it's worth, it could be as simple as a plugged up fuel filter, replace this first! its only $10. be careful with those fuel lines....

If I was in your position and was having a shop do these jobs I would have them do this....

fuel pump and its hanger
fuel filter
anything related to fixing the fuel pump
the entire distributor since it's probably original,
regular paper air filter and oh ya back in the OEM box
spark plugs and wires.
possiboy O2 sensors simply because they are probably also original and getting weak.

I might be missing something but if you change all those things it would have a complete tune up and should be a great running truck. after doing all that on my burb I get 17.8 MPG and I couodnt believe it!

Al
Well I bought the truck, is there some way I can upload a video I took of it running? I think I have a pretty bad problem
 

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1995 GMC K1500 long bed, 305, 5-spd
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Just speculation, but the inability to go bast 30 mph could be a plugged catalytic converter. Had that problem with a 95 Tahoe with the 350.
 

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Well I’m back, still haven’t had any luck finding a first truck but I’m back asking for thoughts on another truck I’m looking at, here are the things I noticed while test driving it, knowing it has misfires;


Took 2 cranks to start up
Motor shakes on idle
Idles hard
Shakes when shifting into Neutral and 2nd, only two I tested
Looses lots of power when releasing pressure on gas pedal
Drives fine otherwise (steering,brakes)
Abs light on, check engine came on a few minutes into drive
Spark plugs replaced recently, done correctly and still changed nothing
Has 5.7L V8 with cold air intake, 2 cherry pack exhaust. 170k miles. Wants 3k for it, will talk him down as he said he’s flexible on price. I know I’m missing some things.

And my concern is it’s going to be to much for me.Luckily labor costs aren’t an issue for me but I don’t want to end up with a blown motor or some other crazy expensive problem. Please let me know your thoughts
The thing I have found is the specific spark type of spark plugs are extremely important,the ignition coils should be replaced all at once not individually been there done that jazz for the last 7 years. Until now. I changed the maf ,fuel filter check injectors,intake manifold leak, it's usually a pain but get a innova 5160 rs it's the life saver you will need. It will pinpoint the issue
 
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